This invention relates to an improvement of the hoist for lifting appliances or block-and-tackle arrangements described in the German Offenlegungsschrift 27 03 384, which is the closest prior art known to applicant. This prior art device has the disadvantage that its pulley-housing comprises a single structure which, in case that it breaks, allows the load to drop to the ground.
In the above referred-to prior art device the pulleys are arranged to opposite sides of a common shaft and if that shaft breaks, the dual cable or rope arrangement becomes illusionary.
It is, therefore, one object of the present invention to provide a mechanism as generally described in the above referred-to German Offenlegungsschrift, but in which the pulley-housing, and the way the load bearing parts are affixed to it, provide perfect security against any possible failures.